Manufacture of lime and gas.



PATENTED AUG. 18, 1903.

J. J. MOTIGHE, DECD.

A. a. M. A. McTIGHB,'EXBCUTRIOES. MANUFACTURE OF LIME AND GAS.APPLIGATION FILED 0OT,5, 1899. RENEWED MAY 2a, 1903.

2 SHEETS-SHEET 1.

NO MODEL.

WM INVENTOR WITN ESSES 5%.... MW

ms Nuflms wzrzas co. PHOtO-LITHQ. wnsumumu. n. c.

No. 736,869. PATENTED AUG. 18, 1903.

I J. J. MOTIGHE, DEOD.

A. a; M. A. McTIGHB, gxncumwns. MANUFACTURE OF LIME AND GAS. APPLICATIONFILED 0012.5, 1399. RENEWED Mums, 190a.

2 SHEETSSHEET 2-,

' aF -l WITNESSES N0 MODEL.

UNITED STATES Patented August 18, 1903.

PATENT OFFICE.

JAMES J. MCTIGI'IE, OF PITTSBURG, PENNSYLVANIA; ANNA MOTIGHE AND MARYADELAIDE MOTIGHE EXECUTRIGES OF SAID JAMES J. MOTIGHE,

DECEASED.

MANUFACTURE OF LIME AND GAS.

$PECIFIGATION forming part of Letters Patent No. 736,869, dated August18, 1903.

Application filed October 5, 1899. Renewed May 25, 1903. Serial No.158,470. (No specimens.)

T 03% whom it may concern:

Be it known that I, JAMES J. MOTIGHE, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a new and usefulImprovement in the Manufacture of Lime and Gas, of which the followingis a f ull,clear,and exact description,reference being had to theaccompanying drawings, forming part of this specification, in whiclFigure 1 is a vertical section of apparatus embodying my invention. Fig.2 is a horizontal section on the line II II of Fig. 1. Fig. 3 is aVertical sectional view of a modification, and Fig. 4 is'-a horizontalsection on the line IV IV of Fig. 3.

The object of my invention is to provide a cheap and eificient processfor the simultaneous manufacture of lime and ()0 gas; and it consists,broadly, in conducting the operation under a commercial vacuum, and bythe term commercial vacuum I mean a decided and material reduction ofpressure obtainable by ordinary improved commercial mechanism as distinguished from the partial vacuum and the chemically-produced vacuum ofthe labora tory.

It consists also in other novel features hereinafter described.

Hitherto in the manufacture of liine (CaO) 3o ithas been customary tocharge the limestone into the well-known limekiln and by the applicationof heat thereto disassociate and drive off by the draft of the burningfuel the carbonic-acid gas ((30,) at atmospheric pressure. This processhas'many disadvantages that are entirely removed by the use of myimproved method,among which disadvantages may be enumerated as follows:First, a very high temperature is necessary at atmos- 40 pheric pressureto disassociate the lime and carbon dioxid, whereas in my method a muchlower temperature may be used, approximately about one-half thetemperature formerly necessary; second, the high tempera ture abovenoted causes the production of what is known as unburned lime, a uselessproduct, formed by the combining of the silica of the limestone with thecalcium, (this cannot form at the low temperature used in the practiceof my method,) and, third, the

for the practice of my invention, in which 2 represents a furnace havinga number of upright retorts 3 3, adapted to contain limestone, and oneor more retorts 4:, adapted to contain coke or coal for the conversioninto carbon monoXid of the carbon dioxid obtained from the retorts Theretorts 8 and 4c are fitted at their upper ends with removablecharging-doors 5, adapted to effect an airtight closure,and each ofthelimestone-retorts 8 is connected by a pipe 6 with the carbonretortat, so that the carbon dioXid generated in the li1nestone-retorts 3 maybe drawn into the upper end of the carbon-retort 4 and downwardlythrough the fuel therein for the purpose of conversion into carbonmonoxid.

At the base of the furnace is a grate 7 for the combustion of fuel forheating the retorts, and the several retorts extend downwardly below thegrate-level and each at its lower end is provided with a door 8 for theremoval ofits contents, these doors, as well as the charging-doors,being adapted to be sealed 8o tightly in order that a partial vacuiimmay be maintained within the retorts during the manufacture of the gas.Near the lower end of the carbon-retort a is an exhaust-pipe 9,connecting with the chamber of a vacuum group, so that a low pressure ismaintained in all the retorts.

The operation is as follows: The retorts 3 are charged with limestoneand the retort I with carbonaceous material, preferably coke, and heatbeing applied these retorts and their contents are raised toincandescence, whereupon the eXlmust-pump in connection with pipe 9 isset in operation, whereby the internal pressure in the retorts isreduced and the gas 5 generated in retorts 3 is caused to flow throughpassages 6 downwardly through retort 4: toward outlet-pipe 9. Theheating of the limestone (caOO causes its disassociation into 00 andOaO. The carbondioxid gas (C0 thus produced is incombustible, but whenit is drawn through the passages 6 and down through the retort 4 itcomes into contact with the hot carbon and combining therewith isconverted into carbon monoxid, the reaction expressed in formula being00 -0200. The gas (00) thus produced passes through the exhaust-pipe 9,being cooled and washed, if preferred, on its way to the gasometer,where Quicklime which is thus made in the retorts 3 is removed from timeto time, and the process will thus furnish an abundant quantity of excellent building-lime. The coke in the retort 4 is gradually consumed bythe passage of the carbon-dioxid gas therethrough, and the ashesresulting therefrom are removed from time to time through a suitablecleaning-door. If bituminous coal be used instead of coke, the resultantgas will be principally CO, with some hydrogen, (C11 the. The exhaustingdevice which I use is preferablya Bunsen or like air pump, whichoperates to chill the gas which passes through the exhaust-pipe and bysuch chilling prevents the gas from returning to the condition of carbondioxid. It will be observed that the coke-retort is heated by the samefuel that disintegrates the CaCO In Figs. 3 and 4 of the drawings I showmy apparatus adapted to the manufacture of combined fuel-gas andilluminating-gas. In this case the retorts 3 3 contain limestone, butinstead of opening into other retorts these limestone-retorts open nearthe upper end directly into the furnace-chamber above the bed of fuel,as shown in Fig. 3. The ash-pit 12 of the furnace is tightly sealed andhas a pipe 13 entering it to supply an air-blast and an exhaust-pipe 14,leading therefrom to the exhaust apparatus. 15 is a vessel containingcrude petroleum or other hydrocarbon and having a pipe 16 leading to theash-pit. 17 is the flue leading from the furnace-chamber for the exit ofthe products of combustion, this flue being equipped with a valve 17 18is a second exhaust-pipe leading to the exhausting apparatus andextending downwardly through the bed of fuel in the furnace to theash-pit 12. The pipes 13, 14:, 16, and 18 are provided with valves V, asshown. The operation of this form of my improvement is as follows: Thefuel in the furnace is brought. to a state of incandescence bycombustion maintained by an air-blast from the pipe 13, thus heating thelimestone-retorts. When the blast has brought the fuel to a state ofincandescence, the stack-valve 17 and the valve of the air-blast pipeare closed and the valve of the exhaust-pipe 14c is opened. Theconsequence is that the carbon-dioxid gas from the retorts by the actionof a vacuum-pump in connection with pipe 14: is sucked down through thebed of incanit assumes atmospheric pressure.-

descent fuel, wherein it is converted to carbon-monoxid gas, which isdrawn off through said pipe 14:, and, as above explained, the partialvacuum maintained in the retorts by the exhausting apparatus greatly,facilitates the action and causes the liberation of the carbon-dioxidgas and its conversion into carbon-monoxid gas more rapidly and with aless expenditure of heat units than otherwise. When the operation lastdescribed has continued long enough to reduce the temperature of the bedof fuel below the working-point, thevalve of the exhaust-pipe 14 may beclosed, the stack-valve 17 and the valve of the airblast pipe opened, soas to cause a blast of air to pass through the fuel and to heat it againto incandescence. Then it is desired to carburet the gas produced bythis apparatus, so that it maybe used as illuminating-gas, I close thevalve of the exhaust-pipe-Mc and open the valve of the exhaust-pipe 18and the valve of the oilpipe 16. The carbonmonoxid gas must then passoff through the pipe 18, but there is mingled with it hydrocarbon gasproduced by the vaporizing of the oil thrown from the pipe 16 into thesuperheated chamber 12, and such hydrocarbon gas passing through theheated pipe 18 is fixed.

WVithin the scope of my invention as defined in the claims myimprovement may be practiced in appliances of other kinds, since- That Iclaim is- 1. The method of making lime and gas, consisting in producinga practical or co1nmercial vacuum, calcining a carbonate of lime thereinand conducting the gas evolved from the lime into contact with heatedcarbon, sub- :00 stantially as descibed.

2. The method of making lime and gas @011- sisting in raising solid fuelto a high heat, by internal combustion, subjecting carbonate of lime tothe heat of such fuel, and passing the 105 gas evolved by the limethrough the same fuel Which is used to heat the lime; substantially asdescribed.

3. The method of making lime and gas, consisting in heating solid fuel,subjecting a no carbonate of lime while under a commercial or practicalvacuum to the heat of said fuel, and passing the gas evolved by the limethrough the said solid fuel; substantially as described.

4. The method of making lime, consisting in producing a practical orcommercial vacuum and calcining a carbonate of lime therein,substantially as described.

I11 testimony whereof I have hereunto set I20 my hand.

JAMES J. MCTIGHE.

Vi tnesses M. S. :MURBHY, CHAs. C. BITTNER.

